Cod sursa(job #1632248)

Utilizator TibixbAndrei Tiberiu Tibixb Data 5 martie 2016 23:17:25
Problema Arbori indexati binar Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.98 kb
#include<fstream>
using namespace std;
int n, m, i, i2, x, y, op, mij, p, u, a[100005], s;
void update(int poz, int val)
{
    for(i2=poz; i2<=n; i2+=(i2&(-i2)))
        a[i2]+=val;
}
int query(int poz)
{
    s=0;
    for(i2=poz; i2>0; i2-=(i2&(-i2)))
        s+=a[i2];
    return s;
}
ifstream in("aib.in");
ofstream out("aib.out");
int main()
{
    in>>n>>m;
    for(i=1; i<=n; i++)
    {
        in>>x;
        update(i, x);
    }
    for(;m--;)
    {
        in>>op>>x;
        if(op==0)
        {
            in>>y;
            update(x, y);
            continue;
        }
        if(op==1)
        {
            in>>y;
            out<<query(y)-query(x-1)<<"\n";
            continue;
        }
        p=1; u=n;
        while(p<=u)
        {
            mij=p+(u-p)/2;
            if(query(mij)>=x)
                u=mij-1;
            else
                p=mij+1;
        }
        query(p)==x?out<<p<<"\n":out<<"-1\n";
    }
    return 0;
}